Human Fibroblasts from Embryonic Stem Cells (image) Cell Press Share Print E-Mail Caption This is a confocal microscopy image of human fibroblasts derived from embryonic stem cells. The nuclei appear in blue, while smaller and more numerous mitochondria appear in red. Credit Shoukhrat Mitalipov Usage Restrictions Credit Required. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.